Distributor breaker plate



March 1953 H. o. WOODS 2,632,818

DISTRIBUTOR BREAKER PLATE Filed Aug. 18, 1949 9o 24- 2 I I 72 a2 68 74 76 a8 86 1/4 66 /o 2 I20 28 0 32 94 A 60 52 98 56 \PJIH 24 a0 68 I0 1 IQ- I awe/14M HOLLAND O WOODS ATTORNEYS Patented Mar. 24, 1953 UNITED STATES r csFicE 10 .gClaims. i

This invention relates'to the ignition systems in use on internal combustion engines such as are used in automobiles, and more particularly to the provision of certain improvements to the existing breaker plate and breaker'point assembly.

It is well known by those skilled in "the art that the performance of internal combustion engines may be varied considerably byadvancing or retarding the-spark at any given engine speed.

It isalso recognized that there is a direct correlation between variations in carburetor throat pressures and the ideal time for inducing the spark in the cylinder. When the engine is .being started, or is idling, carburetor vthroat pressures approximate atmospheric pressure, and a retarded spark is mostadvantageous.

Various devices'are known in'the art-foreccomplishing this retarding andjadvancing of the spark, which actto'rotate'the breakerplate in 1 the distributonso'as to :..cause the fibre rubbing .block on thebreaker point assembly to change its positionarcuately about thecircumference of the rotating cam centrailylocated in the .distributor, thereby ,changing thetiming.

The principal objection to "this type of-construction is that by-so varying the :point of contact of the rubbing block with "the cam faces, the cam'angle and the spark curve are altered beyond the limits specified by the'tenginemanufacturers, to the detriment of the performance of .the engine. The'breaker points'may' also be Worn unduly.

A further objection to the rotating of the breaker plate itself, lies in thefact that the breaker plate sometimes sticks fast within the shell of the distributor casing, thereby causing the'failure of the apparatus, which :will result in having a constant setting of the spark,=-rather .than a variable curve Which ismostdesirable.

It is therefore an object ofthis invention "to provide means for advancing andretarding .the spark in an internal combustion :engine inclu ing a breaker plate'and associatedmovableinterrupter which will maintain ;the breaker-points at their specified reap throughout :the entire .range of theoperation.

A further objectis'toxprovide amovable interrupter which will remain .iree forrotation relative to the breaker :pointassembly.

A further object is to provide amovable interrupter for use with :a breaker plate in an ignition distributorywhich movable interrupter may be formed to'provide :va-rying spark r curves iasdesired.

"Further objects and advantages "of myzinvention will be apparent from a consideration ;of the 'followingspecification in connectionwith the appended claims and accompanying ,;dr,aW- ings in :which Fig. I is a plan view of a distributonshowing my invention, and withthecap and the distributonrotor removed,

Fig. :11 is :a view 6 in section on the time ,II-TII of Fig.1, and

Fig. III is a plan view :of the movable interrupter which cooperates with thebreaker plate andthebreaker point assembly.

:In the drawings .there is illustrated -a distributor housing tflchaving.mountedthereon; bymeans of the plate 82 ;and:the flange 14,;any standard type of spring biased vacuum :control ;unit ,lfB which ;is connected :by :the fitting I8 and the tubularsmember .130 the throat of the .-carburetor. The vacuum control unit is is spring biased in a direction toward the distributor housing [6, and contains theusual diaphragm which'rea'cts to decreasesinpressure in theitube ZG-to impart longitudinal :movement from the housing H] toward the fitting !8.

The breaker 1platej22 is vformed with ,a pairof upstandingiears 24 which permitits attachment to the housing H] by thescrews or rivets26, thereby securing the .abreak'er plate 22 against .rotative movement relative .to .the housing lfl.

The condenser "23 ismounted bathe-plate -i2 by means of a :ground clip-Strand the screw 32, and has the usual. electrical conductor. -employedin the ordinary manner.

The breaker, plate 22 ,is fitted withanaperture 36 positioned relatively closely to the housing I G, fora: purpose as will: appear later. It is likewise fitted with 'theeccentric device- 38, :formed with a screw-head slot it, and with a tap screw hole: positioned to receive the clamping screw 42.

'Centrally disposed with respect to the circular plateZZ is the upstanding bearingboss "flange 44, 'formed with an annular shoulder-48130 position the same with 'respectto'the 'plane'of the "The bearing 44 is "likewise formed with an opening "513 which extends-al- "mostdown to the shoulder st; for a-purposaas will appear later. Centrally disposed with;re-

spectto the housing it, as well as the plate 22 therewith is the timer-cam t!) havinga number of lands =62 and high points or faces 64. It will be appreciated that I have illustrated in Fig. I a cam 66 having 8 high points or faces 64, which is adaptable only for use with an B-cylinder engine. The number of cylinders in the engine and the corresponding number of lands and faces on the timer cam 60 has nothin to do with my invention.

Pivotally mounted on the pivot pin '66 is the usual breaker point assembly 68 which is held in position on the breaker plate 22 by engagement of the clamping screw 52 through the slot Ill and is positioned by use of the eccentric 38 prior to the tightening of the clamping screw 32. The breaker point assembly 59 has an extension :2 and an upturned ear M which supports the fixed breaker point 16. It likewise has an apertured lug I8 which carried the electrical connection 89 which functions in the usual manner in combination with the condenser 28.

The movable contact 82 is mounted on the end of the 'arm 84 which in turn is mounted for pivotal movement about the pivot pin 66 through the insulating block 86. Attached to the arm 84 as by the rivet 88 is the conducting spring 99, which amounts to an extension of the contact arm 84, and extends back around the pivot post 66 and over to the apertured lug 89. The conducting spring 99 urges the rubbing block 92 toward the timer cam 60, and the contact arm 84 therefore responds to movement of the rubbing block 92 as it would alternately engage the lands 62 and the faces 64 of the cam Bil, and thereby moves the contact point 82 into and out of engagement with the contact point 76.

Most of the structure described thus far can be found in many distributors in wide use, and the parts described are not varied in their function or utilization in connection with my invention.

As shown particularly in Fig. 3, I have provided the movable interrupter 94 formed with a lower shoulder 96 and an upstanding annular flange 98 for telescopic engagement over the bearing boss flange 44, and for rotative movement while centered thereon. The shoulder 96 is formed with a flattened portion Iilll to obviate interference with the breaker point assembly 68, while the upstanding annular flange 98 is formed with an opening I02 in a position to correspond with the opening 50 in the bearing 44.

The movable interrupter 94 has fashioned on one side thereof, an extended arm H04 to which is secured an attachment fitting I06 and an axially disposed pin I08 projecting therefrom. It will be appreciated that the lower end of the pin I08 is projected into the aperture 36 for the purpose of limiting the rotative travel of the movable interrupter 94 to the two positions shown in Fig. I. Attached to the upper end of the pin I08 is the actuatingarm I I which passes through a suitable aperture not shown in the casing I0, for operative connection with the diaphragm in the vacuum control unit I6.

It will then be appreciated that under engine operating conditions such as idling in which the pressure in the tube is approximately atmospheric, the spring biased vacuum control unit will urge the actuator I I0 into the full line position shown in Fig. I, thereby giving a fully retarded spark to the engine. However, during normal operation at intermediate speeds the pressure in the tube 29 is considerably reduced, causing the diaphragm in the vacuum control unit I6 to overcome the spring pressure, thereby moving the actuating arm H0 and the extended arm I04 into the dotted line position shown in Fig. I, thereby advancing the spark.

Outwardly disposed from the upstanding flange 98 is an extension arm I I2 having an upstanding ear II4 to which is attached, as by the rivet H6, a resilient strip member I I3 bearing a rubbing block I29 attached thereto by the rivet I22. The engaging face of the rubbing block I20 is positioned to extend through the slot I02 in the flange 98 and through the slot 59 in the bearing 44, and positioned to engage the cam timer 69 and to react therewith. The free end I24 of the resilient strip member I I8 is extended for operable engagement with the rubbing block 92 on the breaker point assembly 68, and is shown, in the drawing herewith, as being an arc of a circle whose center is the axial center of the timer cam 60.

The free end I24 may be curved inwardly toward the center of the cam 60, thereby giving a smaller spark gap at the breaker points I6 and 82, under conditions when the spark is retarded than the gap which would obtain when the spark was advanced. The free end I24 may be curved outwardly with respect to the center of the cam 69, thereby giving a larger spark gap between the contact points 82 and 16 under retarded spark conditions than under conditions wherein the spark is advanced. In other words, the shape of the projecting free end I24 will determine the characteristics of the spark curve available to the engine under various conditions.

In operation, under idling conditions, the parts of the distributor will appear as shown in full line in Fig. I, thereby giving a retarded spark.

Under conditions in which it is desirable that the spark be considerably advanced, the parts will assume the position shown in dotted lines in Fig. I under the urging of the vacuum control unit I6, thereby moving the rubbing block I20 several degrees ahead, thus advancing the spark.

It will be appreciated, that, with the free end I24 of the resilient strip [I8 formed as an arc of a circle centered at the center of the cam 60, the setting between the contact points 82 and 16 will be constant under all of the varying spark conditions between advanced and retarded.

Having described my invention, what I claim as new and desire to protect by Letters Patent is:

1. A distributor plate assembly for use with a distributor casing having an associated spring biased vacuum control unit, comprising a plate member adapted to be attached to said distributor casing, a breaker point assembly adjustably mounted on said plate, a rubbing block on said breaker point assembly, a centrally disposed rotating timer cam projecting through said plate for operative engagement with said breaker point assembly, a movable interrupter centrally disposed for rotative movement about said cam, an operable connection attached to said interrupter and associated with said vacuum control unit and adapted to move said interrupter under the control of said control unit, a second rubbing block mounted on said interrupter for operative engagement with said timer cam, and means on said interrupter responsive to movement of said second rubbing block and adapted for engagement by the first rubbing block whereby said first rubbing block is moved.

2. In a distributor for engine ignition systems having a casing, a distributor plate rigidly mounted therein, a rotating timer cam centrally disposed therein and extending through said distributor plate, a breaker point assembly adjustably mounted on said plate, a rubbing block mounted on a portion of said breaker point assembly and adapted to move one of the contact points of said assembly, and a vacuum control unit operatively associated therewith, the provision of a movable interrupter member centrally disposed for rotative movement about said cam, an operative connection between said interrupter member and said vacuum control unit whereby said interrupter member is rotatively moved in response to the action of said vacuum control unit, a resilient arm attached to said interrupter member for rotative movement therewith, a second rubbing block mounted on said arm and positioned for operative engagement'with said cam whereby a portion of said arm is moved radially toward and away from the center of said cam, and a curved end on said arm adjacent said second rubbing block adapted to be engaged by said first rubbing block to move the latter radialy toward and away from the center of said cam.

3. A movable interrupter member adapted to retard and advance the spark for an engine and for use with a distributor having a housing, a vacuum control unit, operating means responsive to said vacuum control unit, a distributor plate attached to said housing and having a central bearing boss flange, a breaker point assembly having a fixed contact point and a movable contact point mounted on said distributor plate, a rubbing block associated with said movable contact point, and a centrally disposed rotatable timer cam, said movable interrupter member comprising acentral annular guide portion for rotation upon said central bearing boss flange, an arm projecting from said guide portion and connected to said operating means and adapted to impart guided rotative movement to said guide portion, a second arm projecting from said guide portion and adapted .to move therewith, a'contact arm mounted onsaid second arm, a second rubbing block mounted on said contact arm and adapted to engage said rotatable cam, and a curved end portion on said contact arm adjacent said second rubbing block and adapted to be engaged by said first rubbing block whereby said first rubbing block is moved radially toward and away from the center of said cam in response to the movement of said second rubbing block as it engages said cam.

4. In a circuit interrupter for the spark ignition system of an internal combustion engine and incorporating supporting structure, a breaker point assembly mounted on said supporting structure in position to be actuated to intermittently make and break an electrical circuit with an attendant sparking action, said supporting structure including a bearing boss flange, the provision of a timer control member rotatably mounted about said bearing boss flange, means for adjustably moving said timer control member relative to said supporting structure and to the breaker point assembly, means in the form of a camming surface carried upon said timer control member, and means upon said breaker point assembly and engaging along said camming surface whereby the time of actuating said breaker point assembly is capable of being varied to give advanced or retarded ignition by rotating said member on said bearing boss flange and said last means point of engagement with said camming surface is changed.

5. In a circuit interrupter for the spark ignition system of an internal "combustion engine, said circuit interrupter incorporating supporting structure, a breaker point assembly mounted on said-supporting structure in position to be actuated to intermittently make and break an electrical circuit with an attendant sparking action, and a centrally disposed rotatable oam mounted .for'rotating movement at least partially above the plane of said supporting structure, said supporting structure including a bearing boss flange concentric with the axis of rotation of said cam, the provision of a timer control member adapted tobe rotatably mounted about said bearing 'boss flange in position to actuate said breaker point assembly :for the contact making and breaking operations, said timer control member including a flexible arm supporting a rubbing block for operative engagement with said cam and being angularly adjustable to preselected positions for varying the time at which said breaker point assembly is actuated, and a cam surface carried on said flexible arm for actuating the said breaker point assembly.

61; In combination with a distributor plate assembly for use with a distributor casing having an associated vacuum control unit, said assembly comprising a plate member adapted to be attached to said distributor casing, a breaker point assembly adjustably mounted on said plate, a rubbing block on said breaker point assembly, a centrally disposed rotating cam projecting through said plate for operative engagement with said breaker point assembly, the provision of a movable interrupter centrally disposed for rotative movement about said cam, an operable connection attached to said interrupter and associated with said vacuum control unit and adapted to move said interrupter under the control of said control unit, a second rubbing block mounted on said interrupter for operative engagement with said cam, and means on said interrupter responsive to movement of said second rubbing block and adapted for engagement by said first rubbing block whereby said first rubbing block is moved, thereby actuating said breaker point assembly.

'7. In a distributor for engine ignition systems having a casing, a distributor plate mounted therein, a rotating cam centrally disposed therein and extending through said distributor plate, a breaker point assembly adjustably mounted on said plate, a rubbing block mounted on a portion of said breaker point assembly and adapted to move one of the contact points of said assembly, and a vacuum control unit operatively associated therewith, the provision of a movable interrupter member centrally disposed for rotative movement about said cam, a central upstanding bearing member mounted on said distributor plate and adapted to locate and support said interrupter member, an operative connection between said interrupter member and said vacuum control unit whereby said interrupter member is rotatively moved in response to the action of said vacuum control unit, a resilient arm attached to said interrupter member for rotative movement therewith, a second rubbing block mounted on said arm and positioned for operative engagement with said cam whereby a portion of said arm is moved radially toward and away from the center of said cam, and a curved end on said arm adjacent said second rubbing block and adapted to be engaged by said first rubbing block to move the latter radially toward and away from the center of said cam, whereby said breaker point assembly is actuated.

8. A movable interrupter member adapted to retard and advance the spark for an engine and for use with a distributor having a housing, a vacuum control unit, operating means responsive to said vacuum control unit, a distributor plate disposed within and attached to said housing, a centrally disposed bearing boss flange mounted on said distributor plate, a breaker point assembly mounted on said distributor plate and having a fixed contact point and a movable contact point, a rubbing block associated with said movable contact point, and a centrally disposed rotatable timer cam, said movable interrupter member comprising a central annular guide portion adapted to be mounted on said bearing boss flange for rotative movement relative thereto, an arm projecting from said guide portion and connected to said operating means and adapted to impart guided rotative movement to said guide portion, a second arm projecting from said guide portion and adapted to move therewith, a flexible contact arm mounted on said second arm, a second rubbing block mounted on said contact arm and adapted to engage said rotatable cam, and a curved end portion on said contact arm adjacent said second rubbing block and adapted to engage said first rubbing block whereby said first rubbing block is moved radially toward and away from the center of said cam in response to the movement of said second rubbing block as it engages said cam.

9. An accessory for use in an ignition distributor for an internal combustion engine, said distributor having a centrally disposed rotatable cam, bearing structure concentric with the axis of rotation of said cam, a breaker point assembly adapted to be actuated by the lobes of said cam to intermittently interrupt an electrical circuit to cause an attendant sparking action, supporting structure upon which said breaker point assembly is mounted and through which said cam projects, and means adapted to selectively impart rotary movement to said accessory within said ignition distributor, said accessory comprising a movable interrupter mounted for rotative movement upon said bearing structure relative to said supporting structure said breaker point assembly and said cam, means for connecting said movable interrupter to said first means and adapted to move said interrupter with said first means, and a flexible arm on said interrupter adapted to engage said cam and respond to the camming action thereof, said flexible arm being disposed between said cam and said breaker point assembly and adapted to actuate said breaker point assembly and to vary the time at which said breaker point assembly is actuated.

10. In a distributor for engine ignition systems having a casing, a centrally disposed rotatable timer cam, a breaker plate mounted within said casing and defining an aperture through which said timer cam projects, a breaker point assembly mounted on said breaker plate, a movable interrupter mounted in juxtaposition with said breaker plate for rotative movement about the axis of said timer cam, and means responsive to varying engine operating conditions and attached to said interrupter for imparting rotative movement to said interrupter, the provision of a bearing boss flange centrally mounted on said breaker plate, and a guide member centrally mounted on said movable interrupter for telescopic engagement over said bearing boss flange and adapted to position and hold said movable interrupter for rotative movement about said bearing boss flange and relative to said timer cam.

HOLLAND O. WOGDS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Vanderpoel Jan. 27, 1942 

